i have an '02 F-150 with a 4.2L 5-spd and dtock 3.55 pegleg rear. my prob is whenever i get my tires really spining on gravel, or blacktop it hops and shakes violently,and gets real bad in reverse. I dont burnout in the truck, its just when im offroading and i get stuck, or when i play around in the gravel, and break the tires loose. It only happens when the tires spin from a standstill, i thought it was my muffler, but i had a shop weld it on, and secure it. I've seen 60's and 70's muscle cars with serious axle hop, but my truck doesn't have that much power. Any thoughts???, is it normal for my tuck to do that?

 

Check the suspension bushings & fasteners. Then check the shocks.

What do you mean by "dtock" & "pegleg"?

 

sorry,typo...it's a stock rearend, only one tire has traction its not a posi or anything.It doesn't act like their is any suspensiom problems when im on the road,it rides fine and doesnt clunk, its just when the tires spin from a standstill that it does it.

 

An open diff applies power to BOTH wheels. It just sends more to the wheel with less traction. You might find this post interesting.